First in a series of videos about how to write and use your own functions in R. The full series is available as a play list: https://youtube.com/playlist?list=PLD8eCxFKntVHFjlWz30rCeVeSFId2z49f
This material is part of the Functions Lesson in the Data Carpentry for Biologists course. Check out the lesson for exercises to help you practice: https://datacarpentry.org/semester-biology/lessons/R-functions/